Feature TypeDescription
Albedo FeatureGeographic area distinguished by amount of reflected light
CatenaChain of craters
CavusHollows, irregular steep-sided depressions usually in arrays or clusters
ChaosDistinctive area of broken terrain
ChasmaA deep, elongated, steep-sided depression
CollesSmall hills or knobs
CraterA circular depression
FaculaBright spot
FarrumPancake-like structure, or a row of such structures
FlexusA very low curvilinear ridge with a scalloped pattern
FluctusFlow terrain
FossaLong, narrow depression
LabyrinthusComplex of intersecting valleys or ridges
LineaA dark or bright elongate marking, may be curved or straight
LingulaExtension of plateau having rounded lobate or tongue-like boundaries
MaculaDark spot, may be irregular
Mare"Sea"; large circular plain; on Titan, large expanses of dark materials thought to be liquid hydrocarbons
MensaA flat-topped prominence with cliff-like edges
Palus"Swamp"; small plain
PateraAn irregular crater, or a complex one with scalloped edges
PlanitiaLow plain
PlanumPlateau or high plain
ScopulusLobate or irregular scarp
SulcusSubparallel furrows and ridges
TerraExtensive land mass
TholusSmall domical mountain or hill
VastitasExtensive plain
Source - International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN)